Accessible independent housing for people with disabilities: A scoping review of promising practices, policies and interventions

Background Accessible housing is imperative to enabling independent living for many people with disabilities; yet, research consistently shows how people with disabilities often lack appropriate accessible housing and are more likely to experience unaffordable, insecure, and/or poor quality housing. Therefore, the aim of this study was to understand promising practices, policies and interventions regarding accessible independent housing for people with disabilities. Methods We conducted a scoping review that involved searching seven international literature databases that identified 4831 studies, 60 of which met our inclusion criteria. Results The reviewed studies involved 18 countries over a 20-year period. Our review highlighted the following key trends: (1) removing barriers to obtaining accessible housing (e.g., advocacy, builders enhancing housing supply, subsidies and financial incentives); (2) policies influencing accessible housing; (3) interventions to enhance accessible housing (i.e., home modifications, smart homes, mobile applications and other experimental devices); and (4) the impact of accessible independent housing on health and wellbeing. Conclusions Our findings emphasize the importance of accessible housing for people with disabilities and the urgent need to advance accessible housing options.


Introduction
People with disabilities, who represent one of the world's largest minoritized groups, often struggle to find and acquire accessible and affordable housing [1,2].The United Nations Flagship Report on Disability and Sustainable Development Goals highlights that the housing situation of people with disabilities is a key area of challenge over the next decade [3].Approximately 22% of Canadians (some 6.2 million people) have a disability and this number is expected to increase rapidly with Canada's aging population, heightening the demand for accessible housing [4,5].Thus, the magnitude of accessible housing challenges is likely to escalate unless large scale efforts are made to improve the situation and to address issues in the physical housing environment [6].In stating accessible housing throughout this paper, we are referring to housing that has been designed or modified to satisfy applicable accessibility requirements and to account for the needs and preferences of people with disabilities.
Although accessible housing policies exist, they often fail to cover the majority of the housing supply [1].For example, the Center for International Economics [7] estimates that less than 10% of new housing stock has been built to accessible standards.Consequently, many people with disabilities live in housing that does not meet their needs [8] and those who do could face barriers in building relationships with those in their surrounding community (e.g., they may be unable to visit the inaccessible homes of neighbors, friends and family).In Canada for example, people with disabilities are more likely to live in conditions of "core housing need" than the rest of the population, indicating that their housing does not meet a minimum standard of adequacy, suitability, or affordability [9].Many people with disabilities have specific accessible housing requirements, and at the same time have severely limited housing options [10].The lack of accessible housing options can be exacerbated for some people with disabilities who need or prefer to live in close proximity to accessible public transit stations, employment opportunities and everyday services (e.g., health care services, grocery stores etc.).Such a lack of inclusive, affordable and accessible housing perpetuates the marginalization and social exclusion of people with disabilities [11].

Benefits of accessible housing
Accessible housing is critical to the wellbeing of people with disabilities because it can provide them with many health and social benefits for people with disabilities.Indeed, home adaptations are a central part of the rehabilitation process for people with disabilities [12].For example, research consistently highlights that housing accessibility and affordability are important social determinants of health that are associated with improved health outcomes and quality of life [13][14][15][16].Some research demonstrates that interventions to enhance the accessibility of homes (e.g., home modifications, creating space to accommodate mobility devices and implementing accessible designs) can have positive health and social impacts, such as reduced depression, mortality rates, and falls or injuries, in addition to enhanced social participation [2,17].Further, having accessibility related home modifications can improve independence, safety, privacy and self-confidence for people with disabilities [8].Building or adapting homes to an accessible standard could help to reduce costs for health services by decreasing household accidents, the need for institutional care and reliance on other government resources [18].It is therefore critical to understand the most promising practices, policies and interventions that can help to enhance accessible independent housing for people with disabilities.

Challenges acquiring accessible housing
Although appropriate accessible housing enables independent living, research shows that people with disabilities often lack suitable housing, are more likely to experience an increased likelihood of living in unaffordable, insecure and/or poor quality housing and are at a higher risk of experiencing homelessness [10,[19][20][21].People with disabilities often encounter barriers and stigma/discrimination in finding appropriate housing, including learning about available accessible units, securing appointments and receiving reasonable modification requests [22].For example, policies and practices for renting accessible social housing are often complex and difficult for applicants with disabilities to navigate [23].Additionally, home builders often lack an understanding of the basic needs of people with disabilities and are reluctant to innovate or increase costs by customizing accessible homes [24,25].Indeed, there is often insufficient attention paid to design features (e.g., mobility-related, sensory, lighting, sounds, tactile features) that can make housing accessible and liveable for a broad range of needs [1].The scarcity of accessible housing stems from and is supported by widespread and normalized ableism (i.e., disability-related discrimination), which allows the housing needs of people with disabilities to be ignored.The shortage of accessible housing is disconcerting because the United Nations Convention on the Rights of Persons with Disabilities (Articles 9, 28) states that access to adequate, safe, secure, accessible and affordable housing is a fundamental human right [26].Specifically, people with disabilities have the right "to choose their place of residence and where and with whom they live on an equal basis with others" [26].
The severe lack of appropriate accessible housing is worrying because it can lead to several poor health and social outcomes [27].For example, home environments without basic accessibility components can increase the risk of falls, injuries, mortality rates and the use of social services while also restricting social participation, including employment [2,24,28].Indeed, the physical and social characteristics of housing can contribute to disabling and discriminatory environments for people with disabilities [19,25,29,30].For these reasons, there is an urgent demand to improve practices to help match the available accessible housing with people with disabilities who need it the most [23].Synthesizing the promising practices, policies and interventions for increasing accessible independent housing could help to enhance the social inclusion of people with disabilities, while also supporting changes in the dynamics of privilege and marginalization.

Novelty of this review
This scoping review is timely and significant because many nations, including Canada, where the authors are located, are experiencing a housing crisis, which is expected to worsen with rising rental and development costs, increased interest rates and an ongoing shortage of accessible and affordable housing [8].People with disabilities are particularly vulnerable to missing out on acquiring affordable and accessible housing and deserve solutions that enhance their access to appropriate housing.Although the literature on the housing needs of people with disabilities is growing, most of the focus is on elderly populations, those with mental health conditions (and risk of homelessness and 'housing first' programs), and people with developmental or intellectual disabilities living in group homes or supported housing (e.g., onsite-support and services offered to occupants to maintain their well-being) [2,[31][32][33][34][35][36][37].While this research is valuable, there is a critical need to synthesize the most promising practices [38][39][40], policies [41,42] and interventions (e.g., home modifications [17,27,[43][44][45][46], universal design [11,47], architectural planning and design [48], smart home technology [49][50][51], grants and funding [52][53][54] to enhance accessible independent housing for people with various types of disabilities.By doing so, this could help to enhance the social inclusion of people with disabilities, while aiming to shift the dynamics of privilege and marginalization.There remains a concerning lack of knowledge synthesis about accessible independent housing solutions for people with disabilities [8].Focusing on independent housing is critical because most people with disabilities would prefer to live independently [55].The findings of this review could help to inform guidelines and recommendations for the most promising practices, policies and interventions to enhance accessible independent housing options for people with disabilities.

Materials and methods
The research question guiding this review was, what are the most promising policies, practices and interventions for enhancing accessible independent housing for people with disabilities?Our scoping review followed the guidelines outlined by Arksey and O'Malley [56] and subsequently enhanced by Levac et al [57].The strength of a scoping review is its ability to capture a diverse body of evidence, giving a sense of meaning and significance [58,59].This type of review can provide a rigorous and transparent method for mapping the size and scope of a research topic while also synthesizing the findings and identifying directions for future research in a short time span [56,59].Scoping reviews are also useful for assessing the types of evidence that address and inform practice in the field and the way research has been conducted [59].The protocol of this study was not registered as it is not required for scoping reviews.

Search strategy and data sources
The search strategy and database selection were developed through consultation with an experienced research librarian, people with lived experience with a disability and knowledge user advisory group (i.e., people with disabilities, social inclusion and housing expert).A series of international searches for peer-reviewed published literature were conducted using the following six databases including: Avery Index to Architectural periodicals, GEOBASE, Engineering Village, PAIS Index, Scopus, and Web of Science.These databases were selected because they are the most relevant to our research question.Our search involved the following key populations, concepts and contexts: disability (i.e., disability, disabled persons, functional limitation, physical impairment, mobility impairment, sensory impairment, motor impairment, vision impairment, hearing impairment, wheelchair user), accessibility (i.e., accessibility, universal design, built environment, architectural accessibility, facility design construction, adaptation, modification, environment design, smart home technology, adjustment, inclusive design, barrier-free design), and housing (i.e., house, housing, home, living environment, residence characteristics, independent living, life span housing) (see S1 File for full search strategy).Minor modifications to the search strategy were made as required within individual databases.

Article selection
The following inclusion criteria were applied to screen articles for inclusion in this review: (1) a sample of people with disabilities (based on the definition from the International Classification of Functioning, Disability and Health: "an umbrella term for impairments, activity limitations and participation restrictions") [60]; (2) empirical research (i.e., quantitative or qualitative) that has at least one finding focusing on practices, policies, interventions or solutions to enhance accessible (i.e., a home environment that allows a person with functional limitations to get into and out of, circulate within the home and function independently (2)) and independent housing for people with disabilities; and (3) published from January 2002 to December 2022 in a peer-reviewed journal without language restrictions.Two articles included in our review were translated into English using Google translate.The translations were verified by a team member who is fluent in the language.A third team member also read and checked the article to ensure that we derived the appropriate meaning.Additionally, focusing on a 20-year time period is common practice for scoping reviews.
Exclusion criteria included: (1) grey literature (opinions, editorials, books, book reviews and conferences, thesis and dissertations), (2) non-empirical, non-peer reviewed (i.e., grey literature), and (3) research focusing on identifying needs, supported housing, group homes, nursing homes and risk of homelessness among people with disabilities because reviews already exist on these topics [31,32,[34][35][36].We also excluded (4) non-peer reviewed and grey literature because it is more susceptible to bias [61].Additionally, empirical peer-reviewed literature is essential for evidence informed decision-making, policy development and identification of gaps in evidence [62,63].
After conducting the searches across databases and removing the duplicates, the first author imported the article records into Covidence, which is a primary screening and data extraction tool that helps to make the screening process more efficient and transparent.The first author, with expertise in the topic and in review methodology, independently screened all 4831 titles and abstracts, while another researcher screened and verified the excluded studies [59].Next, two authors screened all of the full-texts (n = 191) that met the inclusion criteria.In the end, 60 articles were identified for our review (see Fig 1).Any discrepancies occurring during the screening process were discussed amongst the research team until consensus was reached.A journal of inclusion/exclusion decisions were kept as part of an audit trail (see also Fi 1 for a list of reasons for exclusion).Journal entries were used to formulate discussion points amongst the research team.We documented the screening process using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews checklist (PRIS-MA-ScR) (see S2 File) [64].

Data abstraction and synthesis
Data from all included studies (both qualitative and quantitative) were extracted and compiled by the first author and independently verified by two pairs of authors using a structured predefined abstraction form [59]. Data included information about each study (authorship, year of publication, country, recruitment setting, and design), participants (sample size, age, disability type, and social demographics) and outcomes (e.g., practices, policies and interventions for accessible housing).We used a descriptive analytical method to extract relevant information from included articles.Following the Arksey and O'Malley [56] framework, pairs of authors independently charted the findings of each study by type of practice (e.g., practices, policies, interventions) while focusing on the most promising approaches to improve accessible independent housing.The second stage of analysis involved a 'within study analysis', which consists of a narrative description of each study's findings.Then, we compared and contrasted the findings within and between each outcome.Next, we organized the results by the content of the findings within and across the included studies.This was done by grouping the results by topics and themes related to policies, practices and interventions for enhancing accessible independent housing.Then, the first author synthesized the findings across all of the included studies while also highlighting key trends by participant and disability type.We then summarized and analysed the findings within each study category (e.g., quantitative descriptive frequencies and qualitative content analysis.The research team discussed the patterns across the studies until consensus was reached regarding the final themes for the review.
In two studies most participants lived in subsidized housing [70,86].
The methodological designs of the reviewed studies involved qualitative (i.e., interviews, focus groups, observations and assessments, case study, participatory design) and quantitative (i.e., surveys, secondary analysis of existing datasets, experiment, quasi-experiment and codesign) methods.Among the studies (22/60) incorporating a theoretical framework they included person-environment interaction/fit, ecological model of aging, heterogeneity of characteristics, framework of community practice, neoliberal spaces of exception, social emersion, salutogenic theory, model of competence, diffusion theory, biopsychoecological model, universal design theory, habitation, matching person and technology model, social model of disability, and Andersen's behavioral model.
Our review identified four key themes in the literature: (1) removing barriers to obtaining accessible housing; (2) policies influencing accessible housing; (3) interventions to enhance accessible housing and (4) the impact of accessible independent housing on health and wellbeing.

Theme 1: Removing barriers to obtaining accessible housing
Eighteen studies described approaches to removing barriers to obtaining accessible housing such as advocacy, builders enhancing housing supply, subsidies and financial incentives, in addition to effective communication and collaborative partnerships.
Two studies explained the importance of advocacy to help reduce barriers in obtaining accessible housing [98,100].For example, in a survey of city planners in the US, Lehning [98] found that advocacy was an effective strategy to reduce barriers and encourage municipal governments to adopt housing innovations.In particular, their study discovered that cities experiencing public advocacy or having a higher percentage of the population with a disability had increased odds of adopting community design innovations [98].Another study [100] highlighted that in their effort to increase the supply of accessible homes, people with disabilities in the US needed to advocate and appeal to the capitalist side of home builders in advocating for universal design by emphasizing its profitability [100].
Builders enhancing the supply of accessible housing.Although many studies mentioned increasing the supply of accessible housing, three studies focused on this directly [97,102,103].For example, two studies described how home builders facilitated the supply of accessible housing [97,102] and one study focused on the removal of barriers in ordinary housing stock [95].For instance, Kaminski et al. [97] explored the visitability of houses in one area of California and explained that builders began to voluntarily include visitability components in their houses, which could have resulted from a marketing campaign targeted toward builders to make accessibility features more attractive.Additionally, Imrie [102] evaluated the reactions of home builders to government regulation concerning disabled people's access to new housing in England and Wales where 41.9% of home builders reported they provide a sufficient supply of accessible dwellings [102].Meanwhile, Pettersson et al. [95] estimated the effects of targeted elimination of environmental barriers in ordinary housing stock in Sweden and reported the largest effects were for multi-dwelling blocks and single-family houses (especially for houses built before 1960).
Subsidies and financial incentives.Seven studies described the use of financial incentives or subsidies to increase the supply of availability of accessible housing [53,76,81,86,88,98,100].For example, Lehning [98] explained how advocating for accessible housing innovations amongst city planners in the US included financial incentives (i.e., incentives to make housing accessible, developer incentives for housing units).Meanwhile, Hoffman et al. [86] evaluated the effect of a housing voucher program for non-elderly people with disabilities in the US.They reported that the program provided housing vouchers to subsidize rental costs and enhanced access to community based services [86].A study exploring the longitudinal changes in housing accessibility among clients with various types of disabilities receiving grants for housing adaptations in Sweden found significant improvements in accessibility and usability of housing [76].Additionally, having financial incentives for different housing provisions and incentives for individuals to stimulate relocation were highlighted in a Swedish study involving housing stakeholders [88].In particular, subsidies targeting the improvement of current housing stock and interventions focusing on accessibility could be advantageous for housing accessibility [88].Another study explored housing adaptation grants among a sample of people with various disabilities in Japan noted they were implemented amongst 15.6% of their sample [53].Meanwhile, Fallon and Price [81] examined the preferences and satisfaction for aging-in-place amongst a sample of people with disabilities in the US who lived in subsidized housing (i.e., low-income housing tax credit program) and explained that residents prioritized affordability and safety.Another financial incentive, the Mountaineer Mortgage Plus Renovation program, offered in a rural area in Ohio US, allowed for the cost of a renovation or home improvement within a mortgage loan, enabling people with disabilities to make necessary modifications to live in their own homes [100].
Effective communication and collaborative partnerships.Seven studies explained how having effective communication and/or collaborative partnerships could reduce barriers to acquiring accessible housing [23,54,69,79,88,96,100].For example, in a UK-based study, Nord et al. [69] explored what constitutes good communication in designing home bathroom adaptations (e.g., new layout and non-slip flooring) and found that a client's trust in their occupational therapist was important for establishing and maintaining a successful dialogue during the housing adaptation process [69].Other researchers discussed the usefulness of having knowledge about housing adaptations, including knowing who to contact for facilitating the process, amongst a small sample of adults with functional limitations in Sweden [79].Participants in this particular study described the benefits of having a collaborative team of professionals (along with input from the client) to develop the best solutions for housing adaptations [79].
Another element of reducing barriers to accessible housing involved effective communication including connecting people with disabilities to accessible housing, often through a matching process.For example, effective communication was also highlighted in a UK-based study with families raising a child with a disability where some reported that being listened to and respected were important components of the housing adaptation process [96].In another study, applicants for accessible and adapted homes in the UK used a matching approach, which they found helpful, especially when they had a single point of contact to assist them through the process, accessing up-to-date property information and the option for virtual viewings [23].Effective matching of disabled housing applicants to accessible household properties included renting vacant properties, recovery of properties no longer occupied by a disabled person, nominations through registered social landlords, and renting newly built accessible units [23].
Having collaborative partnerships was another salient aspect of enhancing accessible housing.For example, in interviewing housing stakeholders in Sweden, Heller et al. [88] explained that having effective dialogues and collaboration with various stakeholders could help enhance accessible housing.Another study, focusing on government representatives in Australia, similarly emphasized the importance of developing partnerships for viable accessible housing options and understanding contemporary responses and shared learning amongst key stakeholders [54].Further, Danko [100] described that developing collaborative partnerships (e.g., builders, money lenders, landlord associations, major building suppliers), consumer guides, model programs (e.g., especially disseminating information about universal design and accessibility), and incentives with housing professionals could help reduce barriers to obtaining accessible housing [100].

Theme 2: Policies influencing accessible housing
Seven studies in our review focused on policies influencing accessible housing for people with disabilities [54,82,88,98,100,104,105]. For example, Dunn [104] described the evolution of government implemented independent living policies for people with disabilities in Canada and highlighted that barrier-free housing, which is currently in short supply, can assist people with disabilities to live independently.In another study, Semeah et al. [82] found that certain housing policies (e.g., Fair Housing Amendments Act, reasonable modifications, and subsidized housing) facilitated access to rental housing among US veterans with disabilities.Additionally, Danko et al. [100] highlighted that the Community Reinvestment Act in West Virginia, US could facilitate low income individuals with disabilities to obtain accessible housing.Under this Act special programs for people with disabilities are not needed because the majority of banks within this region providing service to low-income individuals, including people with disabilities.Moreover, people with disabilities and their families, living in a rural US state, suggested that enhanced building code enforcement could help to reduce barriers and facilitate access to accessible housing [100].Another US-based study described how the existence of a policy entrepreneur (i.e., those who work within government to advocate for policy innovations) in a city was positively associated with innovation in housing adoption [98].
In a study exploring how municipalities in Sweden addressed housing accessibility issues and the types of policy solutions considered among housing stakeholders, it was reported that housing accessibility involved renovations and maintenance, individual adaptations, and collaboration with private housing stakeholders regarding housing provision [88].In a Chinese-based study explored factors that facilitated the adoption of policy innovation on major housing adaptation by provincial governments and found that diffusion mechanisms could either help or hinder the adoption of major housing assessment policy innovations by governments [105].Moreover, a study [54] examined factors for decision-making and service impacts related to housing and support for people with disabilities in Australia and New Zealand and discovered that insurers influence decisions to fund housing.Specific factors influencing their decisions included understanding demand, working within legislation and rules and individual needs [54].
Twelve studies described common household modifications to enhance accessibility, which often involved entrances, bathrooms, kitchens and bedrooms [8,43,55,68,[70][71][72]77,91,101,106,107].For example, a study focused on people with mobility disabilities in Thailand, Sukkay [106] found that bathrooms and bedrooms were the two most important rooms to adapt [106].Meanwhile, Goodwin et al. [8] discovered that common home modifications, among a sample of Australians with mobility impairments, included step-free entrances, wider internal doors and corridors, level access (i.e., no stairs throughout the home) and increased bathroom space.Other accessible household design features included entrance to outdoor spaces, larger room sizes, non-slip flooring, and heights of features and appliances around the home [8].Similarly, in their study of older adults with spinal cord injuries in Sweden, Norin et al. [68] found that the kitchens (i.e., wheelchair accessible stovetops), main entrances (i.e., ramps) and hygiene areas were common locations for housing adaptations.Further, occupational therapists who conduct home assessments in Australia highlighted that the most important housing features included step-free showers, grab bars, and reinforced bathroom walls, as well as having bedroom space on the ground floor [91].Similar findings were shown in Bishop et al.'s [72] study where they evaluated the prevalence of housing modifications among American adults with multiple sclerosis and found that the most common modifications involved the bathroom (i.e., grab bars and shower and toilet modifications).Other home modifications noted in this study included entryways (i.e., ramp, grab bars, porch/deck modifications) living area, interior stairs (i.e., lift chairs and elevators), doorways (i.e., widening and lever handles), bedroom (i.e., expanding room or moving room to ground floor), kitchen (i.e., lowering or modifying the cabinets and countertops) and flooring (i.e., replacing carpet with hardwood) [72].Moreover, people with mobility disabilities in the US reported that changes to the bathroom were the most frequent home modification followed by changes to facilitate cleaning, improve safety, home entrance and mobility within the home [77].Likewise, for older adults using a walker in New Zealand, Kuboshima and McIntosh [55] highlighted the following design elements and considerations for accessible home modifications: layout of space to avoid needing to turn around in small enclosed spaces, removing ground-level floor differences, minimizing interior doors, avoiding sharp corners, locating door handles, sufficient space in bathrooms and garage, and L-or I-shaped kitchens.Similar renovations were noted among a sample of Koreans with physical disabilities where most home renovations involved safety handles and grab bars, removing door sills and stepped pulleys, replacing wallpaper and finishing materials.Interestingly, this study noted more requests for lighting, thermal environments and improved humidity control in rural areas than urban [43].
Common household modifications differed slightly for people with vision loss.For example, older adults with vision impairments in the UK used adaptive strategies using color contrast on steps and around light switches, and underfloor heating to help reduce the risk of tripping and falling [70].Participants in this study familiarized themselves with their new surroundings by using techniques such as mind mapping, tactile stickers, removing trip hazards, installing non-slip flooring and eliminating door saddles [70].The importance of lighting in the home for people with sight loss was examined from practitioners' perspectives where they emphasized that lighting should be appropriate, sufficient, even, adjustable, sustainable, energy efficient, simple and adaptable [101].Additionally, for those with visual impairments in the UK, Rooney et al. [107] explored the perceived suitability and effectiveness of lifetime homes (i.e., aging-in-place strategy) and found they offer benefits (e.g., future-proofing features, extra space, and sight loss features).Moreover, Kutintara et al. [71] designed and evaluated a kitchen for people with visual impairments in Bangkok and discovered that people attending cooking courses were able to cook safely in the kitchen.Participants reported they preferred sliding cabinet doors with a shelf inside and D-shaped drawer pulls in addition to contrasting colored strip edges on the kitchen counter [71].
Eight studies described factors affecting household modifications to enhance accessibility [72][73][74]84,85,93,99,109].For example, Aplin et al. [85] interviewed participants with various disabilities (and other family members and caregivers) in Australia to understand what aspects of their home environment impact home modification decisions.They reported four key dimensions commonly affecting home modifications, including personal (i.e., safety, privacy, freedom, independence), societal (i.e., costs, service provider and government standards for public access, visitability), physical (i.e., space and dimensions within the home), and temporal (i.e., health status, future growth of family).They also noted that social (i.e., visitability) and occupational (i.e., self-care and domestic activities) dimensions were additional factors impacting home modification decisions [85].Similarly, a Spanish-based study explained that environmental, economic and functional factors are most relevant in determining adaptations [93].In particular, their study found that households from bigger cities, richer regions and people with more severe disabilities were more likely to spend money on home adaptations [93].De-Rosende-Celeiro et al. [74] explored the role of environmental factors in predicting the implementation of bathroom adaptations among older adults with disabilities in Spain and found that social functioning was significantly associated with adaptations.Moreover, people with greater degrees of mobility limitations had an increased likelihood of making a housing modification [72].
Meanwhile, in a small sample of parents of disabled children in Australia, they explained how their decisions to modify their house and purchase equipment were made to enhance their child's independence and included installing a sensory garden, a spa to enhance physiotherapy treatment, adapted kitchens and bathrooms, and moving to a more accessible home that allowed freedom of movement and access to the community [84].Another study explored people with physical disabilities in Thailand and noted that people who had a lower extremity impairment or poor balance were more likely to implement housing adaptations [109].Further, Luther et al.'s [73] study identified five client profiles (based on age and extent of disability) for housing adaptations among a sample of older adults with disabilities in Sweden to understand how home based interventions could be delivered more effectively.In particular, they emphasized the diverse needs of people applying for housing adaptations and the importance of having client profiles to guide professionals on how to differentiate home-based interventions [73].
Another factor affecting home modifications included enhanced training for those who design accessible housing.For example, two studies explored training among architectural students who engaged in a valuable universal design learning exercise with user-experts and explained that it shaped their thinking about universal design and meeting the needs of elderly and disabled clients, as well as their aim to enhance accessible housing [99,113].
Smart homes, mobile applications and other experimental devices.Six studies reported on the implementation of smart homes to enhance accessibility [49][50][51]94,110,111].For example, Ding et al. [50] explored practitioner's perspectives on how smart home technology is becoming affordable and relevant for improving environmental control and independence for people with disabilities in the US.They highlighted several common practices relating to smart home service delivery (i.e., importance of client-centered approach, informal service delivery process, trial and error of setting up technology).Their study also emphasized factors affecting smart home service delivery including the influence of client familiarity with technologies and existing use of technology on service delivery, the importance of conducting needs and ability assessments, demonstrating or trialling the technology, client training and device customization [50].Similarly, Oyegoke et al. [110] developed an innovative smart solution to streamline the housing adaptation process for people with disabilities in the UK.Their "Adapt-ABLE" approach used optimization techniques through an information system allowing for the development of a preventive measure that can access a suitability index of homes for the occupants.In Tayyaba et al.'s [111] study focused on "internet of things" devices for smart homes for people who are blind, they reported that a model smart home with sensors and antennas can generate warning signals about obstacles and help the user to navigate their home safely.
Kosmyna et al. [94] conducted an experiment to assess a smart home control mechanism involving the use of a brain-computer interface among a sample of young adults in France.Their study uncovered that users with disabilities could control lighting, television, coffee machine, and shutters in the smart home (i.e., 81% accuracy versus 77% task accuracy for those without a disability) [94].Meanwhile, Chen et al. [49] explored the impact of an eyeglass type infrared based home appliance system for people with spinal cord injury and tetraplegia and they found no significant differences in the accuracy and average time cost of the control and experimental groups.They noted that their novel home appliance control system had advantages of convenience, accuracy and sanitation to allow people with spinal cord injury to live more independently [49].An additional study evaluated the treatment of a smart home enabled by intelligent solutions among a sample of people with various disabilities in Slovenia and found statistically significant improvements in functional independence scores and occupational performance scores [51].
Mobile applications also helped to enhance accessible housing, as outlined in two studies [4,92].In particular, one study by Helle et al. [92] combined two separate apps that targeted professionals and seniors to improve housing accessibility and housing provisions in a sample of older people in Sweden.They described the development of a user-friendly and acceptable prototype that included design features that differed between professionals (i.e., wanted a design that supported extended functionalities) and seniors (i.e., who wanted a simple and easy to use interface) [92].In another study, Jonsson et al. [4] co-designed and evaluated a new decision support system to inventory decision-making for improved accessibility for multifamily housing in Sweden and highlighted that their app has potential to support multi-usable professional inventories of environmental barriers, and areas for accessibility improvements.
One study described the development and implementation of an experimental device to enhance accessible housing.Specifically, Mattie et al. [65] explored how a sample of people with mobility disabilities in Canada viewed existing home access solutions that they trialed such as stairs, a ramp, a platform lift, a stair glide lift and a newly designed experimental device (called ARISE).They found that over 80% of participants were satisfied with the ramp and platform lift.They underscored home access features that a majority of participants (90%) considered important: ease of use, ability to use independently, safety and security [65].Most participants rated the newly designed prototype as their most preferred device [65].

Discussion
Scholars have considered a range of promising practices, policies and interventions aimed at enhancing accessible independent housing for people with disabilities.Focusing on this topic is salient because access to adequate housing is a fundamental human right [26] and an essential element that can enable independent living and community participation and is closely linked with enhanced health and wellbeing [13,14,16].Most previous reviews that have considered barriers to obtaining accessible housing have not focused on independent housing; rather they have focused on barriers to other types of housing such as group homes and supportive housing.
Our review highlighted several practices regarding accessible independent housing such as enabling home modifications and removing barriers to obtaining accessible housing at both the societal and individual levels through such things as increasing housing supply, financial incentives, advocacy, effective communication and partnerships.Our findings align with other research showing that home modifications can play a key role in addressing some of the consequences of inaccessible housing [11].Previous research has consistently shown that increasing awareness about the needs and rights of people with disabilities can help to enhance attitudes and behaviours towards them [114].Additionally, people with disabilities could also benefit from increased awareness of (and more direct connections to) potential accessible housing options and financial incentives that are available to them [72].Previous research on accessible housing has highlighted the importance of effective communication between housing stakeholders and people with disabilities, especially involving the latter in the co-design of house modifications [18].Other research similarly emphasizes the importance of partnerships and collaboration between housing stakeholders and people with disabilities and take their design preferences into consideration [33].It is essential to engage people with disabilities in program and policy planning to ensure that accessible housing solutions and adaptations meet their needs.It is also evident from the findings of our review that much further advocacy, training and education regarding accessible housing provision and its benefits is critically needed across a range of housing stakeholders (e.g., builders, contractors, planners, designers, architects, real estate professionals, landlords, bank employees, policy decision makers, clinicians doing home assessments).Such training could equip these stakeholders to develop more accessible housing designs, and more streamlined processes for finding and obtaining accessible independent housing and, in turn, they could produce enhanced accessible independent housing options that many people with disabilities desire [100].Further, it was interesting to note that most of the financial incentives that were described in the studies in our review targeted individuals with disabilities while much less attention was paid to potential incentives for builders and other housing stakeholders to provide accessible housing.
The findings of our review drew attention to some policies influencing the availability of accessible housing, such as fair housing acts, and policies related to modifications and subsidized housing for people with disabilities.Although we noticed many descriptions of policies for accessible housing in the course of our review, most of them were not evaluated.Other research highlights how policies to increase the supply of accessible housing are limited and there is often resistance from developers and builders and other housing stakeholders [41,102].Additionally, preventive policies such as creating accessibility inventories are essential to ensure that accessibility is addressed before the need arises and strategies targeting relocation are essential [88].There is also a critical need for key policy decision-makers and other housing stakeholders at various levels of government (municipal, provincial and federal) to work together to develop and implement effective policies that can help to enhance accessible housing options for people with disabilities.Some researchers argue that a wider adoption of universal design approaches to housing is required to enhance the availability of accessible homes [102].Further work is needed to evaluate how effective existing policies and practices are with respect to their impacts on enabling people with disabilities to obtain accessible independent housing.
Our review has identified some interventions that can enhance accessible housing such as smart homes, mobile applications and experimental devices.Although the interventions highlighted in our review show promise, there is an urgent need for more solutions and interventions to enhance the supply of accessible housing and simplify the laborious processes that people with disabilities must go through to obtain suitable housing (e.g., more matching interventions, the creation of mobile applications that help people with disabilities to find appropriate housing).It will be important to also consider the affordability of accessible housing and whether it is located within safe communities that offer accessible transport options and services [33].Additionally, a secondary finding of our review emphasized the impact of accessible independent housing on health and wellbeing for people with disabilities, which is consistent with other literature showing how home modifications can help with injury prevention, improved function, independence, physical health and wellbeing and social participation [2,17].

Limitations, risk of bias and future directions
Although our review was comprehensive and included seven databases without language restrictions, it could be possible that some relevant studies were missed.Also, our review did not include grey literature as it was beyond the scope of our study, and thus we may have missed other potentially relevant accessible housing policies.Second, most studies focused on physical and mobility impairments while there was much less attention to other types of disabilities (e.g., sensory, hearing, vision impairments, brain injury, autism etc.).Future research should explore this gap in further depth.Third, it is important to recognize that perceptions, the treatment of people with disabilities and the availability of supports (including accessible housing and related policies) vary across the 18 countries (mainly higher-income) that were included in our review.It would be worthwhile for further studies to explore the relationships between accessible housing policies and the disability / civil rights laws by country.Fourth, the participant characteristics and methods of the included studies varied widely and the findings of this review should be interpreted with caution.More diverse samples (i.e., gender, racial and ethnic diversity) are needed to explore how socio-demographic characteristics could impact needs and solutions for accessible housing because it is not a one-size-fits all approach.Future research should consider exploring what practices and interventions work best for whom (e.g.considering socio-demographic characteristics), the optimal time to implement them, their cost-effectiveness and in what contexts (e.g., socio-political and individual (rent versus homeowner etc.) they can be applied.Additionally, there was very little research focusing on children and youth with an assumption that people who need accessible housing are elderly.Future research should consider focusing specifically on the housing experiences and perspectives of children and youth because they likely have different needs than older adults.Finally, there was surprisingly little attention paid to affordability of accessible housing.Exploring this aspect further is critical because housing affordability is increasingly an issue of growing concern, particularly for marginalized populations such as people with disabilities [115].As such, more in-depth research is needed that explores factors affecting home modifications and the ability for people with disabilities to obtain accessible housing.

Conclusions
This scoping review a range of promising practices, policies and interventions regarding accessible independent housing for people with disabilities over a 20-year period.Our findings uncovered four prominent themes within the literature: (1) removing barriers to obtaining accessible housing; (2) policies influencing accessible housing; (3) interventions to enhance accessible housing (i.e., home modifications, smart homes, mobile applications and other experimental devices) and (4) the impact of accessible independent housing on health and wellbeing.The evidence in this review suggests that there are potential promising practices, policies and interventions to enhance accessible housing through home modifications, smart homes, mobile applications, and experimental devices, which could help to enhance the quality of life of people with disabilities.There is a critical need to continue to advocate and find accessible housing solutions for people with disabilities.Future research should consider focusing on marginalized and minoritized groups who may be more vulnerable to securing accessible housing.